package com.jm.offer.easy;

import java.util.ArrayList;

/**
 * @Description
 * @date 2022/4/20 8:02
 */
public class _29顺时针打印矩阵 {

    public static void main(String[] args) {
        int[][] matrix = {{1,2,3},{4,5,6},{7,8,9}};
        int[] ints = spiralOrder(matrix);
        for (int anInt : ints) {
            System.out.println(anInt);
        }
    }

    public static int[] spiralOrder(int[][] matrix) {
        if(matrix.length == 0) {
            return new int[0];
        }
        /**
         * 声明四个边界
         *  left
         *  right
         *  top
         *  bottom
         */
        int l = 0, r = matrix[0].length - 1, t = 0, b = matrix.length - 1, x = 0;
        int[] res = new int[(r + 1) * (b + 1)];
        while(true) {
            for(int i = l; i <= r; i++) {
                res[x++] = matrix[t][i]; // left to right.
            }
            if(++t > b) {
                break;
            }
            for(int i = t; i <= b; i++) {
                res[x++] = matrix[i][r]; // top to bottom.
            }
            if(l > --r) {
                break;
            }
            for(int i = r; i >= l; i--) {
                res[x++] = matrix[b][i]; // right to left.
            }
            if (t > --b) {
                break;
            }
            for(int i = b; i >= t; i--) {
                res[x++] = matrix[i][l]; // bottom to top.
            }
            if(++l > r) {
                break;
            }
        }
        return res;
    }
}
